Delta Air Lines will add new service from Seattle-Tacoma International Airport, including nonstop service to Phoenix Sky Harbor International Airport and seasonal nonstop service to Palm Springs International Airport.

Delta will also add new and expanded service fromSeattle to seasonal destinations as it continues building its domestic network.

Delta’s new Seattle service beginning Dec. 20, 2014 includes:

Five daily flights to Phoenix

One daily seasonal flight to Palm Springs, Calif.

Saturday seasonal service to Tucson, Ariz.

Saturday seasonal service to Jackson Hole, Wyo.

One additional nonstop flight to Honolulu for a total of two daily flights

Expanded seasonal service beginning in September includes:

One new daily nonstop flight to Anchorage, Alaska for a total of two daily flights in September and three daily flights during the summer

Delta’s new service to Phoenix, Palm Springs and Tucson will be operated by Delta Connection carrier SkyWest Airlines using two-class, 76-seat aircraft, while Jackson Hole service will be operated with two-class, 65-seat aircraft. The expanded Honolulu and Anchorage service will be operated by Delta using Boeing 757 and Boeing 737 aircraft, respectively.

“As Seattle’s fastest-growing airline, we’ve doubled the number of flights we offer from a year ago to provide our customers more choice and flexibility when traveling from these key markets to the Pacific Northwest,” saidMike Medeiros, Delta’s vice president – Seattle. “This service will offer one-stop access for customers to the top international destinations while providing local travelers with more options during the winter months.”

By this summer, Delta will offer more than 2,500 daily international seats as part of its 79 peak-day departures to 25 destinations.

In addition to the expanded service, Delta will also adjust current arrival and departure times in Seattle to offer easier connections for customers traveling through the hub.

Delta recently announced expanded Seattle service from Anchorage; Fairbanks, Alaska; Juneau, Alaska; Las Vegas; Los Angeles; Portland, Ore.; San Diego; San Francisco; San Jose, Calif.; and Vancouver to support its growing international gateway that currently operates nonstop flights to Amsterdam, Beijing, Paris-Charles de Gaulle, Shanghai-Pudong and Tokyo. The airline will also begin operating new nonstop international service this year to London-Heathrow beginning in March as well as Hong Kong and Seoul in June, pending government approval.

Every long-haul international Delta flight from Seattle now features full flat-bed seats in BusinessElite, Economy Comfort seating and entertainment on demand in every seat throughout the aircraft.

Delta currently operates 34 peak-day departures to 15 destinations from Seattle, and every flight offers BusinessElite/First Class and Economy Comfort seating as well as domestic Wi-Fi service. The airline has also invested $14 million in its facilities at Sea-Tac, including its recently completed lobby renovations, new Delta Sky Club, Sky Priority services, new gate area power recharging stations and expanded ticket counters.